Home canning can reduce our exposure to pesticides and preservatives. It can help save money, and it can be rewarding to grow your own food. It allows people to preserve tastes that you just can't find in a grocery store (surely your own chili tastes better than a can off the grocery store shelf). Home canned items also make great gifts.
The water bath processing method is fairly simple and inexpensive. The filled canning jars are placed in the canner, which has enough hot water in it to cover the jars. The water is brought to boiling and held at that temperature for the time specified in the canning recipe. However, this method is only safe for certain foods.
If a food is naturally high in acid (most fruits for example) or if acid is added to the food (for example the vinegar in pickles), then the acid helps to prevent the growth of bacteria. The heat from the boiling water is enough to destroy any harmful organisms that can survive in the acid.
If the food is low in acid content (vegetables for example) then the temperature of boiling water is not enough to destroy the harmful bacteria that can live in these foods. Although it is more expensive, a pressure canner should be used for these foods. By increasing the pressure, we also raise the boiling point of the water and thus increase the temperature at which the food is processed.
For somebody who is new to canning, the "Ball Blue Book" has been a reliable source for generations. Some other sources that are very good are "The Food Lover's Guide To Canning: Contemporary Recipes & Techniques" by Lucy Clark Crawford, and "Complete Guide to Home Canning and Preserving" by the U.S. Department of Agriculture.
Charlotte Wingert ([http://www.homecanningjars.com]) writes a blog that includes basic instructions for home canning, and canning recipes